When there are two variables with the same name but different scope, i.e. one is a local variable and the other is a global variable, the compiler will give preference to a local variable.
In order to access the global variable, we make use of a “scope resolution operator (::)”. Using this operator, we can access the value of the global variable.
Example:
#include <iostream>
using namespace std;
// Global variable declaration:
int g = 20;
int main () {
// Local variable declaration:
int g = 10;
cout << g; // Local
cout << ::g; // Global
return 0;
}​
Output :
10
20
